Self-cleaning cut-off gate construction



July 31, 1962 s. T. TRANSEAU SELF-CLEANING CUT-OFF GATE CONSTRUCTION Filed Aug. 24

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INVENTOR.

s E M TRHNSEHU 3,47,ll6 Patented July 31, 1962 Free 3,047,006 SELF-CLEANING CUT-OFF GATE CGNS'IRUCTlON Sherman T. Transeau, R31, Riverside, NJ. Filed Aug. 24, 1959, Ser. No. 335,508 8 Claims. (Cl. 137-243) The present invention relates generally to conduit systems and more particularly to improvements in valves of the gate shut-off type adapted to be used in vacuum and pressure conveying systems for the handling of various materials.

In its most general aspects, the present invention relates to a low head room valve of the type which includes interconnected main body portions respectively provided with coaxially aligned passages therethrough, these passages terminating in closely spaced peripheral edges between which are disposed a shittable shut-off gate in the form of a flat plate, one portion of which is apertured to provide a through opening which may be presented in and out of registry with the axially aligned passages through the valve body.

Among the principal objects of the present invention is that of providing in a valve a self-acting means operative constantly to resiliently press the shut-01f gate flatwise against a fiat seating surface formed at the inner edge of the passage through the valve body which is located on the upstream side of the shut-off gate, thereby efiectively closing the conduit against flow of material therethrough when the shut-01f gate is shifted into its valve closing position.

Another important object of this invention is to provide a cut-off gate valve of the type wherein the shiftable gate plate is entirely enclosed within an airtight gate body and is provided with means operable externally of the body for shifting the gate into opened or closed position, and wherein the valve body is provided with means for automatically removing any material which may have accumulated therein and which may tend to adversely offset the operating elficiency of the valve.

Still another object of this invention is to provide an air and dust tight valve which is internally provided with a shiftable gate plate and in which the plate is constantly under such bias in one direction that when it is disposed in valve closing position the passage through the valve is efieotivley sealed oif regardless of whether the gate plate is mounted for operation in a vertical or a v horizontal plane and regardless of whether the conduit in which the valve is incorporated is under pressure, as in the case of a pressure operated conveying system, or under vacuum, as in the case of a vacuum system.

The foregoing and other objects of the invention will become apparent from a careful reading of the following specification in conjunction with an examination of the accompanying drawings, wherein:

FIGURE 1 is a plan view of a valve constructed in accordance with and embodying the principles of the present invention; 7

FIGURE 2 is a vertical sectional view as taken along the lines 22 of FIGURE 1;

FIGURE 3 is a vertical sectional view as taken along the lines 33 of FIGURE 1;

FIGURE 4 is a horizontal sectional view as taken along the line 44 of FIGURE 2, and shows certain details of the cut-off gate and the gate biasing pressure ring construction;

FIGURE 5 is a fragmented sectional view, enlarged for clarity, as taken along the line 5-5 of FIGURE 4, and more clearly shows detailed structure of the gate biasing pressure ring assembly.

In these several figures, like elements are denoted by like reference numerals.

Referring now to the drawings, and more particularly to FIGURES 1, 2 and 3 thereof, it will be observed that the valve therein illustrated, designated generally by the reference numeral 10, comprises a pair of main valve body parts 11 and [12, which serve as supporting frames for the intervening shut-off gate 13 in the form of a swingably mounted fiat plate of generally elliptoidal outline and having an opening 14 in one end portion thereof.

The gate frames 11 and 12, which are best characterized as being of generally semi-elliptoidal external shape, are secured together along their marginal edges by a series of bolts and nuts 15 to provide a relatively shallow, airtight casing for the shut-ofi? gate 13, the frame being respectively provided with axially aligned passages with which the opening 14 of the shut-elf gate is adapted to register when the valve is operated to open the conveying line for the free passage of material therethrough.

More specifically, the gate frame 11, which for descriptive purposes may be considered the upstream frame because it is normally disposed on the upstream side of the shut-off gate, is cast or otherwise formed to provide a main body member 16, having a thickened bolting edge 17 and a circular neck 18, the latter being disposed with its axis extending normal to the general plane of the body member 36 and located substantially on the minor axis of the semi-elliptoid and outward toward the curved edge thereof. The neck portion 18 of the upstream gate frame 11 is flanged at its outer end, as at 19, to facilitate bolting of the frame to the correspondingly flanged part of the conduit (not shown) of which the valve forms a part, while the inner end of the neck portion 18 is in the form of an internal annular projection 20. The central passage 22 through the neck 18, of course, is in constant registry with the interior of the conduit immediately associated therewith.

The downstream gate frame 12 is generally similar in construction and is also provided with a main body part 23 having thickened bolting edge 24 and a circular neck portion 25 which is adapted for coaxial registry with the neck portion 18 of the upstream gate frame 11. As in the case of the gate frame 11, the neck portion 25 of the gate frame 12 is flanged at its outer end, as at 26, for bolting thereof to the correspondingly flanged part of the conduit on the downstream side of the valve, the downstream portion of the conduit being, of course, in registry with the passage 27 through the neck 25.

It will be noted that the inner end of the annular projection 20 of the gate frame 11 is machined as at 28 to provide a flat surfaced seat marginally surrounding the passage 22, and that the seat is axially spaced from the internal projection 21 in the gate frame 12 a distance just suificient to accommodate more or less freely the shutoff gate plate 13 with the upstream face of the latter underlying the seat 28.

In order to insure sealing engagement of the upstream face of the shut-off gate 18 with the flat surface seat 28 of the gate frame 11, the neck portion 25 of the downstream gate frame 12 is externally annular-1y recessed radially outwardly of the internal projection 21 which lies immediately below the shut-off gate 13, and disposed within this recess is an annular gate biasing pressure ring 34 biased upwardly against the shut-01f gate 13 by means I of a plurality of peripherally spaced compression springs 35, each of the springs 35 being seated upon the shoulder of the recess in the neck portion 25 and being secured from lateral shifting by means of pins 36 secured into the pressure ring'34 and extending downwardly into the central opening of the coil spring 35. Thus, the shut'otf surface is inflat contacting relationship with the seat 28 formed on the annular'projectio-n 20 of the upstream gate frame 11. The expanded fragmentary view of FIGURE 5 most clearly shows the foregoing described details of the gate biasing pressure ring assembly. As best seen in the showing of FIGURE 4, four of the biasing springs 35 are seen to be symmetrically spaced about the periphery of the biasing pressure ring 34, but it is to be realized that a greater number of such springs could be utilized, as for example six or eight or even more, should the desired upward biasing pressure be greater than that achievable with only four springs as illustrated. The number of such springs utilized, and the spring constant designed into each spring, are of course determined by the particular application of the valve.

The upstream gate biasing arrangement illustrated is utilized because of the presence of the self-cleaning vents 40 best seen in the showing of FIGURE 2, where it will be observed that the gate body regionlying outwardly from the passages 22 and 27 is connected downwardly through the passages 40 and into the outlet passage 27 in the downstream gate body member 12 through aper- V tures in the neck portion 25. These self-cleaning vents dition arises by virtue of the fact that when the aperture 14 in the shut-oif gate 13 is swung into registry with the passages 22 and 27 to allow passage of material through the gate, and the gate 13 is subsequently swung into gate closing position as illustrated in FIGURES l, 2 and 3, a certain amount of material will be carried laterally sideways within the confines of the aperture 114. Repeated openings and closings of the valve would eventually carry sufiioient conduited material into the lateral portions of the valve main body that eventually the shut-01f gate 13 would be precluded from shifting by virtue of a barrier of such packed material. The occurrence of such a condition, of course, requires that the system be shut down and the valve dismantled to clean out the packed material and restore free action to the shut-off gate 13. However, by providing the selfcleaning vents 40, it becomes at once apparent that material carried laterally outward into the gate body by motion of the shut-ofi? gate 13 is prevented from accumulating and eventually giving rise to the undesired packed condition, since material so carried laterally outward will fall of its own weight downwardly into the vents 4G and flow or be drawn into the outlet passage 27 where it rejoins the main body of the conduited material.

Understanding now the purpose and function of the selfcleaning vents 40, the reason for the upstream biasing of the shut-off gate 13 becomes clear. It is apparent that if the reversed condition existed, namely, downstream biasing of the shut-off gate 13', there would exist a leakage passage from the upstream inlet passage .22 laterally outward over the top surface of theshut-off gate 13 and downward into the outlet passage 27 through the selfcleaning vents 40. Such action would, of course, defeat the purpose of the valve and is avoided by the upstream biasing of the shut-off gate 13. Of course, in the event that the self-cleaning vents 40 were not incorporated into the gate valve, then the shut-off gate 13 would be biased in a downstream direction in systems where either vacuum were applied from the downstream side or Where pressure were applied on the upstream side, so that the pressure or the vacuum would aid in maintaining a gate seal. The arrangement as illustrated in the figures would typically be utilized in a system wherein vacuum is maintained on the upstream passage 22 so that suchv vacuum again aids in biasing the shut-elf gate 13 into sealing engagement when the valve is shut, the vacuum being rendered ineifectual when the gate was open to allow gravity flow of conduited material from the upstream to the downstream side of the valve.

The shut-oil gate 13 is provided at the center of one side thereof with a laterally projecting portion 29, which is suitably reinforced as at 30, to mount an operating shaft 3-1. The shaft portion 31a. is loosely projected through the shut-ofi gate 13 and reinforcing portion 30 and keyed thereto in any convenient fashion, as for example by squaring theshaft portion 31a and the aperture through which it projects in the shut-ofi gate, so that relative vertical movement between the shaft 31 and the shutofi gate 13 is permitted while at the same time maintaining a keyed relationship between the two so that rotation of the shaft 31 is enabled to effect shifting of the cutoil gate 13 for purposes of presenting the aperture 14 therein into and out of registry with the valve conduit passages 22 and 27. The shaft 31 extends upward througha stuffing box gland 32 fitted in the body 16 of the gate trame 11 and is provided at its outer end with a squared extension 33 for reception of an operating lever (shown in phantom) for oscillation of thegate plate into valve opening or closing position. The shaft 31 is also formed. with a bottom circular extension 3 8 journalled for rotation in a shaft seat 39 threaded into the body 23 of the gate frame 12.

Having now described my invention in connection with a particularly illustrated embodiment thereof, it will be apparent that the invention is susceptible of various changes and modifications which may be made from time out departing from'the general principles or real spirit tion to provide a space between the proximate inner ends thereof, a cut-oi? gate in the form ofyan apertured flat plate disposed in said space for shifting movement laterally of said axially aligned conduit sections, one of said ,sections on the upstream side of said gate plate being provided with a fiat-surfaced seat against which the upstream face of said plate is adapted to be seated and the other of said sections on the downstream side of said gate plate being externally provided with an annular shoulder spaced axially from the plane of shifting of said gate plate, an annular pressure ring in axially spaced registry with said annular shoulder, a plurality of compression springs spaced circumferentially about said shouldered conduit section and disposed between said ring and shoulder to constantly bias said gate plate into fiat-wise sealing engagement with said flat-surfaced scat, means for automatically preventing conduited material from packing be tween said ring and shoulder to thereby avoid eventual.

binding of said gate plate, and means for laterally shifting said cut-off gate plate to position the aperture therein into i and out of registry with said aligned conduit sections open and close the valve as desired.

2. In a cut-01f valve as defind in claim 1 wherein said pressure ring is provided with means operative to respectively locate and operatively retain said compression springs in their circumfereutially spaced relation as aforesaid.

3. A cut-off valve for use in a material conveying conduit system comprising, in combination, a pair of axially aligned conduit sections disposed in axially spaced relation to provide a space between the proximate ends thereof, a cut-oif gate in the form of a fiat plate swingable in its own plane within said space and having an aperture therein adapted to be brought into and out of registry with said aligned conduit sections, spring-pressed means operative to constantly bias said gate plate into flat-wise:

sealing engagement with the end of the conduit section disposed to the upstream side of the gate plate, and a ma terial-collecting chamber conjointly formed by said conduit sections, said chamber being disposed to one side of and in free communication with the interior of the conduit section downstream of the gate plate whereby any material entering said chamber upon swinging movement of the gate plate is free to be discharged therefrom into the conduit system downstream of said gate plate.

4. in a cut-off valve as defined in claim 3 wherein said collecting chamber is provided with an enlarged materialreceivin opening located in close proximity to the plane of swinging movement of the gate plate and with a reduced material-discharging opening extending through the wall of the conduit section downstream of the gate plate, said chatnber being further provided with an external sloping wall to facilitate gravity discharge of material there rom.

5. in a cut-off valve as defined in claim 4 wherein a pair of said collecting chambers are provided at opposite sides of the conduit section downstream of the gate plate.

6. A cut-oil valve for use in a material conveying conduit system comprising, in combination, a pair of axially aligned conduit sections disposed in axially spaced relation to provide a space between the proximate ends thereof, means on said conduit sections conjointly providing therebetween a chamber surrounding said space, a cut-off gate in the form of a flat plate swingable in its own plane about a pivot spaced laterally of said space and having an aperture therein movable through said space along an arcuate path into and out of registry with said aligned conduit sections, spring-pressed means operative to constantly bias said gate plate into fiat-wise sealing engagement with the end of the conduit section disposed to the upstream side of the gate plate, and a material discharge port communicating said chamber with the interior of the conduit section downstream of the gate plate whereby any material entering said chamber upon swinging movement of the gate plate is free to be discharged therefrom into the conduit section downstream of said gate plate.

7. in a cut-oil valve as defined in claim 6 wherein the arcuate line of travel of the center of the gate plate aperture is substantially coincident with the center of the opening into said discharge port.

8. In a cut-off valve as defined in claim 6 wherein a pair of said discharge ports are provided at opposite sides of the conduit section downstream of the gate plate and in the path of travel of the gate plate aperture.

References Cited in the file of this patent UNITED STATES PATENTS 727,236 Wallis May 5, 1903 743,511 Huxley Nov. 10, 1903 2,805,836 Taylor Sept. 10, 1957 2,907,342 Berg Oct. 6, 1959 FOREIGN PATENTS 295,520 Great Britain Aug. 16, 1928 678,124 Great Britain Aug. 27, 1952 

